Flushing Brakes Without First Drain/ Refill Master

[2civics]

Is there any technique which allows you to flush your brakes by pumping the brakes, bleeding out the old nasty stuff from the bleeders, and just topping off the master cylinder with fresh fluid?

I thought you always turkey baster out the master cylinder and replace with fresh fluid before you begin bleeding procedure.

I know this to be true in my head and if so, I have to have it redone in my 2011 civic because all my mechanic did was top off the old fluid as he went without first removing the old fluid. The car has 27k miles and is 5 years old. (The old fluid was golden.)

Thanks for any help in advance.

 

[SwampSurvivor]

That's what I have always done ...

I'm sure I have had to pump 3 or 4 extra times but that's fine.

 

[Leo99]

You don't have to remove what you can from the master cylinder with a turkey baster, you can push all the old fluid through the bleeders.

 

[2civics]

Originally Posted By: Leo99
You don't have to remove what you can from the master cylinder with a turkey baster, you can push all the old fluid through the bleeders.


So the old fluid should have been replaced one way or another, correct? Through the bleeders or through the combination of cylinder/ bleeders? Reasoning....old fluid becomes corrosive/ absorbs water?

Well I know he didn't draw all the old fluid through the bleeders because he only used less than a half can of brake fluid to do the job.

 

[andyd]

I figure on using a qt of dot 3-4 when I flush the brakes. The stuff you want to get rid of is the muck at the wheel cylinders.The stuff at the top of the system isn't the problem.

 

[2civics]

Originally Posted By: andyd
I figure on using a qt of dot 3-4 when I flush the brakes. The stuff you want to get rid of is the muck at the wheel cylinders.The stuff at the top of the system isn't the problem.

So I'm okay?

Doesn't the fluid in the cylinder get corrosive?

 

[demarpaint]

I siphon out fluid from the master cylinder, just enough not to get air in the lines and refill it with fresh fluid. Then I go to the right rear caliper open the bleeder and drain about 8 ounces of brake fluid, making sure to keep the master cylinder topped up. Then I move to the left rear, right front, and finish with the left front. I let gravity bleed off about 8 or so ounces of brake fluid from each caliper, and be sure to keep the master cyl. topped up. I use a little over a quart to complete the job.

As andyd said: "The stuff you want to get rid of is the much at the wheel cylinders."

Next time I do it I will probably use my Miti-Vac.

 

[2civics]

Originally Posted By: demarpaint
I siphon out fluid from the master cylinder, just enough not to get air in the lines and refill it with fresh fluid. Then I go to the right rear caliper open the bleeder and drain about 8 ounces of brake fluid, making sure to keep the master cylinder topped up. Then I move to the left rear, left front, and finish with the right front. I let gravity bleed off about 8 or so ounces of brake fluid from each caliper, and be sure to keep the master cyl. topped up. I use a little over a quart to complete the job.

As andyd said: "The stuff you want to get rid of is the much at the wheel cylinders."

Next time I do it I will probably use my Miti-Vac.


The nasty stuff near the bleeders was drained out. So what should I do about the master cylinder? Just topped off, not siphoned out before hand.....? This step that you and others do was skipped. Will I be alright? He used about 6 oz of brake fluid to do the job.

 

[2civics]

You both are telling me, I think, that I am fine. Yet at the same time it would have been ideal to replace the fluid in the master cylinder, but that it isn't necessary. Maybe just be sure I do it next time?

 

[demarpaint]

Originally Posted By: 2civics
Originally Posted By: demarpaint
I siphon out fluid from the master cylinder, just enough not to get air in the lines and refill it with fresh fluid. Then I go to the right rear caliper open the bleeder and drain about 8 ounces of brake fluid, making sure to keep the master cylinder topped up. Then I move to the left rear, left front, and finish with the right front. I let gravity bleed off about 8 or so ounces of brake fluid from each caliper, and be sure to keep the master cyl. topped up. I use a little over a quart to complete the job.

As andyd said: "The stuff you want to get rid of is the much at the wheel cylinders."

Next time I do it I will probably use my Miti-Vac.


The nasty stuff near the bleeders was drained out. So what should I do about the master cylinder? Just topped off, not siphoned out before hand.....? This step that you and others do was skipped. Will I be alright? He used about 6 oz of brake fluid to do the job.



I siphon the fluid from the master so I'm getting some of the dirty fluid out before I start the job. A lot of people skip that step, and as long as you bleed enough from the left rear caliper [the contents of the master cylinder, and caliper] that should be fine. I did it the way I was taught that's all. I always start at the left rear wheel, the furthest from the master cylinder. I did hear certain vehicles suggest starting at another wheel, but that doesn't apply to mine, so I don't know the exact details of which vehicles or why.

If you did 6 ounces of fluid to do the entire job he probably didn't get all of the dirty fluid out of the system. 6 ounces at each wheel might be OK.

 

[2civics]

Originally Posted By: demarpaint
Originally Posted By: 2civics
Originally Posted By: demarpaint
I siphon out fluid from the master cylinder, just enough not to get air in the lines and refill it with fresh fluid. Then I go to the right rear caliper open the bleeder and drain about 8 ounces of brake fluid, making sure to keep the master cylinder topped up. Then I move to the left rear, left front, and finish with the right front. I let gravity bleed off about 8 or so ounces of brake fluid from each caliper, and be sure to keep the master cyl. topped up. I use a little over a quart to complete the job.

As andyd said: "The stuff you want to get rid of is the much at the wheel cylinders."

Next time I do it I will probably use my Miti-Vac.


The nasty stuff near the bleeders was drained out. So what should I do about the master cylinder? Just topped off, not siphoned out before hand.....? This step that you and others do was skipped. Will I be alright? He used about 6 oz of brake fluid to do the job.



I siphon the fluid from the master so I'm getting some of the dirty fluid out before I start the job. A lot of people skip that step, and as long as you bleed enough from the left rear caliper [the contents of the master cylinder, and caliper] that should be fine. I did it the way I was taught that's all. I always start at the left rear wheel, the furthest from the master cylinder. I did hear certain vehicles suggest starting at another wheel, but that doesn't apply to mine, so I don't know the exact details of which vehicles or why.

If you did 6 ounces of fluid to do the entire job he probably didn't get all of the dirty fluid out of the system. 6 ounces at each wheel might be OK.


I agree with you on the 6 ounces. Making an appointment with a mechanic in the morning. Nothing like paying twice. Thanks for the help.

 

[slacktide_bitog]

Speed bleeders

 

[demarpaint]

Originally Posted By: 2civics
Originally Posted By: demarpaint
Originally Posted By: 2civics
Originally Posted By: demarpaint
I siphon out fluid from the master cylinder, just enough not to get air in the lines and refill it with fresh fluid. Then I go to the right rear caliper open the bleeder and drain about 8 ounces of brake fluid, making sure to keep the master cylinder topped up. Then I move to the left rear, left front, and finish with the right front. I let gravity bleed off about 8 or so ounces of brake fluid from each caliper, and be sure to keep the master cyl. topped up. I use a little over a quart to complete the job.

As andyd said: "The stuff you want to get rid of is the much at the wheel cylinders."

Next time I do it I will probably use my Miti-Vac.


The nasty stuff near the bleeders was drained out. So what should I do about the master cylinder? Just topped off, not siphoned out before hand.....? This step that you and others do was skipped. Will I be alright? He used about 6 oz of brake fluid to do the job.



I siphon the fluid from the master so I'm getting some of the dirty fluid out before I start the job. A lot of people skip that step, and as long as you bleed enough from the left rear caliper [the contents of the master cylinder, and caliper] that should be fine. I did it the way I was taught that's all. I always start at the left rear wheel, the furthest from the master cylinder. I did hear certain vehicles suggest starting at another wheel, but that doesn't apply to mine, so I don't know the exact details of which vehicles or why.

If you did 6 ounces of fluid to do the entire job he probably didn't get all of the dirty fluid out of the system. 6 ounces at each wheel might be OK.


I agree with you on the 6 ounces. Making an appointment with a mechanic in the morning. Nothing like paying twice. Thanks for the help.


No problem. The job is an easy DIY job.

 

[JHZR2]

I think it will just take a lot longer and use a lot more fluid, because all the junky fluid in the MC, which is moist and dark quite often, will have to flow through first...

 

[2civics]

Originally Posted By: JHZR2
I think it will just take a lot longer and use a lot more fluid, because all the junky fluid in the MC, which is moist and dark quite often, will have to flow through first...


That's the thing, it may have been moist but it was as golden and new looking as right out of the bottle.

 

[Rand]

That bad part is by the wheel cylinders. If you got all that out.. I'd just wait a couple years and do it again.

I usually siphon the reservoir and refill with fresh but that's not really the "bad stuff" you need to get out.

 

[jrmason]

I would be much more concerned with all the gunk sitting in the bottom of your calipers. The fluid in the calipers see all the heat cycles and is where you have the best chance of finding moisture. It will not be removed by simply bleeding the brakes, the clean fluid enters the caliper at the mid point and exits out the top via the bleeder leaving contaminated fluid at the bottom along with any traces of moisture that may be present. One must first remove the calipers one at a time and open them up with a C clamp to evacuate all the old fluid, then once all have been evacuated you can now proceed with the flushing of the lines. I invite anybody that thinks this is unnecessary to pull a caliper after a typical "flush" and evacuate the fluid from the caliper. You'll be surprised at what comes out even though you may be getting clean fluid out the bleeder while doing the flush.

Good luck getting a mechanic to do this unless you have a good one, most are in too much of a hurry and are more concerned with getting your car out of the bay so they can get the next one in.

 

[HTSS_TR]

Originally Posted By: demarpaint
Next time I do it I will probably use my Miti-Vac.

I tried both Motive power bleeder and Mityvac 7201, Mityvac is much better than Motive power bleeder.

 

[demarpaint]

Originally Posted By: HTSS_TR
Originally Posted By: demarpaint
Next time I do it I will probably use my Miti-Vac.

I tried both Motive power bleeder and Mityvac 7201, Mityvac is much better than Motive power bleeder.


You were instrumental in me buying my Miti-Vac. Once again many thanks! A brake fluid swap is one thing I haven't done with it, yet. I'm due for rear brakes and a brake fluid swap this fall in my Jeep. I will be using it then for sure.

 

[ac_tc]

Vacum bleeding is a tool that should be used wizely...
they can pull air into the brakes by the seals and you will get a soft and spoongy pedal- not good.
they may be quick but gravity bleeding is a great way.( preassure bleeding seems good to but i never tried it..)
Another good tip is to press the pistons back into the caliper with the blleders open to get the collected muck out.
Do the change when servicing the pads.
Im also a friend of sucking any old fluid out of the reservoir.
If a bleeder is completly unservicable, push that piston in, empty the reservoir and fill it again, pump the piston out ( be careful here so you dont go to far and it´ll pop out. put it on the disck with the worn pads as a safe measure.)repeat a couple times.